若3n²减n=1,求6n³+7n²减5n+2003的值
来源:学生作业帮助网 编辑:作业帮 时间:2024/06/24 05:12:15
![若3n²减n=1,求6n³+7n²减5n+2003的值](/uploads/image/z/4744224-0-4.jpg?t=%E8%8B%A53n%26%23178%3B%E5%87%8Fn%3D1%2C%E6%B1%826n%26%23179%3B%2B7n%26%23178%3B%E5%87%8F5n%2B2003%E7%9A%84%E5%80%BC)
若3n²减n=1,求6n³+7n²减5n+2003的值
若3n²减n=1,求6n³+7n²减5n+2003的值
若3n²减n=1,求6n³+7n²减5n+2003的值
3n²-n=1
则
6n³+7n²-5n+2003
=6n³-2n²+9n²-3n-2n+2003
=2n(3n²-n)+3(3n²-n)-2n+2003
=2n+3-2n+2003
=2006
6n³+7n²-5n+2003
=9n²-3n+2003
=2006